Musings on Geology

Musings on Geology

David A. Plaisted


The problem we would like to consider is how one can explain the characteristics of the sedimentary rocks found in vast deposits all over the world. We are primarily interested in the paleozoic and mesozoic deposits. These sediments are close to parallel to one another for large thicknesses and often contain many fossils. Many of these fossils are marine, and in addition there is often not much evidence of erosion between the layers. There are exceptions, but during a process as violent and catastrophic as the biblical flood, it would not be surprising for erosion and crustal movements to occur. Of course, processes since the deposition of sediment could also cause breaks in them. The layers of sediment (that were obviously flat when they were deposited) often extend for hundreds of miles. These facts are visible to all, but their significance is often missed.

Let us consider processes today that are depositing sediments and see whether they can account for these features. One process is the deposition of sediments in river deltas. Now, river deltas are affected by the current of the outflowing water, and so are not completely level. In addition, the accumulation of sediment causes the river to extend further and further out into the ocean, so that the layers would not continue to accumulate in the same location and parallel to one another for millions of years. Geologists appear to recognize this.

It is also possible for sediments to be deposited in lakes by ordinary inflow of water. Again, the bottoms of lakes are generally not level, and as lakes are also affected by water currents, one would not expect successive layers of sediment to be so parallel to one another as is often observed for many hundreds of feet. The sediment would be deposited preferentially near the inflow of water as in a river delta, and the lake would soon fill up. In fact, the lakes existing today are for the most part filling with sediment and will not last for long. So this could not account for millions of years deposits of sediment, either, as required by conventional geologic time scales.

In addition, lakes must have borders, but the sediment found in nature is not bordered by other rock structures. Rather, the sediments just continue on indefinitely in all directions.

One possibility is that these sediments were laid down on the bottom of the ocean. This would require a flat ocean bottom for millions of years, over large areas of the earth's surface, which seems implausible. Also, this would suggest a quiet environment, which does not seem compatible with the rapid burial required for fossils. In addition, many fossils are of organisms that live on land. Finally, most sedimentary deposits are found on the continents and not in the ocean.

Now, some deposits can be laid down by the action of wind in a dry area. However, there is no way this could explain the frequent occurrence of fish fossils in the sedimentary layers. As noted above, fossils do not form unless the organism is buried rapidly, suggesting a flood.

So we consider the possibility that these sedimentary layers were deposited by floods. A flood into a lake could deposit a flat layer of sediment over a large area, and by repeated floods, many such layers could accumulate, fossils included. However, the borders of the presumed lake are not in evidence, as noted before. Of course, erosion could remove the borders, but some traces should remain. Also, that would have to be one deep lake to be able to fill up with sediments for millions of years and not dry up.

It is also possible to have floods depositing sediments on dry land, such as in a valley. But then one still has to explain the relative lack of erosion between the layers. This might be explained if this was a desert region, for example, but with periodic floods. But even flood waters run off, and produce erosion in this way at the conclusion of the flood. No edges to the valley are found in the sediments, either, but the sediments extend on and on in all directions. Also, if there were multiple floods in a desert region, where do all the marine fossils come from? This could only occur if there were a lake or river higher up that deposited them, but this seems unlikely in a desert region. Furthermore, many of the fossils are of creatures that do not indicate a desert region, such as carboniferous forests with giant insects. So we have to discard this possibility, too.

We can imagine that the ocean rose and fell repeatedly over millions of years, depositing marine fossils in an otherwise arid area in which little erosion would occur. But then the rise and fall of sea level would have to be explained in some manner, and also the relative lack of erosion between the layers. Also, with floods of this nature, one would expect to have a moist area, and this would encourage plant and animal growth between the layers of sediment, but this is not seen. In fact, many of the fossils suggest a moist, rich environment, inconsistent with this scenario. With so much moisture, one would expect more erosion, especially over millions of years. Finally, much of the sediment is inorganic matter that must have had a source (a mountain or a volcano) and must have been transferred to the area for millions of years. This source has disappeared from the geologic record without a trace, and the transport of inorganic matter to the layers of sediment implies processes of erosion which however are little in evidence. There are igneous deposits, but as far as I know, no volcanic mountains.

At this point I have run out of plausible possibilities extending over millions of years. The only other possibility I can imagine is that all of these sediments were deposited in a short time by a global flood which brought many marine fossils onto the land. This would explain how the sediments could be parallel, extend over hundreds of miles, contain so many marine fossils, and have so few evidences of erosion in between. There also would have been eruptions of lava during this time. We may not understand all the details of how such a flood could work, but it is clear that sediments entering a body of water in rapid sequence from various locations will deposit many parallel layers of sediment with different kinds of fossils and little erosion in between. So we see that a worldwide, catastrophic flood in which the sea rose and fell in a relatively short period of time is the most reasonable explanation of the facts, regardless of how much it is ridiculed by the scientific community.

It is interesting that geologists are recognizing more and more that much of the geological sequence was not laid down slowly, but rather very fast. However, they believe that this was done not by a single worldwide catastrophe, but by a sequence of local ones, because of the so-called "unconformities" that are sometimes found between layers.

Let me comment briefly on these unconformities between layers. These are places where one geologic layer is tilted relative to the next one, indicating some erosion and passage of time in between the layers. However, these unconformities are not cosynchronous all over the world. This means that for any two successive geological layers A and B, there is somewhere in the world where they are laid down without significant evidences of erosion between them. Assuming as geologists do that geological layers are deposited simultaneously all over the world, this would imply that the whole geological sequence was laid down rapidly at one time.

A more detailed discussion of the subject matter of this article can be found here.

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